We’ve all been happy-facing and sad-facing like fury ever since Facebook launched ‘Reaction’ buttons – but what are they actually FOR?

Answer: if you throw out a lot of Angry Face – or any of the other emoji now on offer – you might be changing what you see in News Feed.

Facebook has said that it hopes to use the Reactions to ‘tune’ what we see in News Feed – so we ‘see stories we want to see’.

Some have voiced fears that the system may lead to people only ever seeing stories they ‘agree with’ – or that it might weed out bad news.

Facebook Reactions Product Manager Sammi Krug, says, ‘Our goal with News Feed is to show you the stories that matter most to you. Initially, just as we do when someone likes a post, if someone uses a Reaction, we will infer they want to see more of that type of post.

‘In the beginning, it won’t matter if someone likes, “wows” or “sads” a post – we will initially use any Reaction similar to a Like to infer that you want to see more of that type of content. Over time we hope to learn how the different Reactions should be weighted differently by News Feed to do a better job of showing everyone the stories they most want to see.’

Facebook also said that the new buttons are ‘an opportunity’ for publishers and advertisers.

Krug said, ‘We see this as an opportunity for businesses and publishers to better understand how people are responding to their content on Facebook.